"But our research shows that when a person feels implicated in a product's failure – think building Ikea furniture – they're more likely to shift blame to the product when complaining and increase ill will toward it."

In an experiment, subjects were divided into two groups and directed to replicate the preparation of an "award-winning smoothie." All of the participants were set-up to fail with poor quality food processors.

Half the group was made to feel the smoothie failure was their fault and the other half was told that it was likely a machine malfunction.

Participants primed to believe the failure was their fault rated the machine lower on a nine-point scale after complaining – 3.29 – versus the same participants who were not given the chance to complain – 4.31.

Participants primed to blame the processor rated the device higher after given the chance to complain – 4.02 versus 3 out of nine.

A further experiment showed that when self-blamers were provided with affirmative statements about their competence, they became more likely to rate a product favourably after complaining – 5.22 versus 3.36 on a nine-point scale.

"With companies turning to social media to communicate with consumers, the power of customer complaints has been amplified," says Professor Dahl. "Our study shows that companies shouldn't just let people sound off. They need to be stroking egos, as well."